猪生殖—呼吸道综合征病毒（PRRSV）CH—1a株糖蛋白基因的遗传变异分析

新近发现的猪生殖－呼吸道综合征病毒（ＰＲＲＳＶ）是单股ＲＮＡ病毒,属于不久前成立的动脉炎病毒科,为了比较国内分离的ＣＨ－１ａ株与国外毒株的分子遗传学关系,扩增并克隆了ＰＲＲＳＶ ＣＨ－１ａ株糖蛋白基因ＯＲＦ２￣５,测定了其核苷酸序列。用序列分析软件分析了其编码产物的分子量、等电点、疏水性、抗原性和有关位点,并与国外毒株进行了序列比较和系统发育进化分析。结果表明：ＣＨ－１ａ株与ＶＲ－２３３２株尽管密

Genetic Variation Analysis of Genes Encoding for Glycoproteins of Porcine Reproductive and Respiratory Syndrome (PRRS) Virus Strain CH-la

Porcine reproductive and respiratory syndrome (PRRS) virus is a newly recognized single stranded RNA virus belonging to the recently approved family Arteriviridae. The RNA genome of PRRS virus consists of 8 open reading frames (ORFs). Previous studies have shown that PRRS virus strain CH 1a, a Chinese reference strain, is characterized to be North American genotype. In order to further clarify the genetic relationship between CH 1a and other strains, the strain CH 1a ORFs 2 to 5, the relatively variable genes encoding viral glycoproteins, were amplified, cloned and sequenced. Molecular analysis of the predicted encoding product was performed with the aid of several software packages. The results showed that though strain CH 1a is closely related to strain VR 2332, the prototype of North American genotype, however, there are considerable variations between the two strains. We suggest, strains CH 1a and VR 2332 represent two different subtypes within North American genotype.